DIAMINE  COLOURS 

COUPLED  WITH  NITRAZOL  C 
ON  COTTON  YARN 


CASSELLA  COLOR  COMPANY 

182  and  184  Front  Street, 

NEW  YORK. 

Boston:  39  Oliver  Street. 

Philadelphia:  126  and  128  South  Front  Street. 
Providence:  64  Exchange  Place. 

Atlanta:  47  North  Pryor  Street. 

Montreal, Canada,  59, William  Street. 


No.  3447 


On  account  of  the  liability  of  Nltrazol  C,  pat.,  to  spontaneous 
combustion,  we  do  not  carry  this  article  in  stock.  Wherever  the 
use  of  same  is  mentioned  in  this  hand-book,  we  recommend,  in- 
stead, the  use  of  diazotized  Paranitraniline,  for  the  coupling  of 
our  colors.  The  final  result  is  exactly  the  same. 

CASSKblyA  COIyOR  COMPANY. 


DIAMINE  COLOURS  COUPLED  WITH  NITRAZOL  C 

ON  COTTON  YARN. 


The  cotton  is  dyed  in  the  manner  customary  for  Diamine  Colours, 
for  about  one  hour  in  a boiling  bath,  with  the  addition  of  y2 — 1%  soda 
ash  and  10 — 20%  desiccated  Glauber’s  salt. 

The  stated  quantities  of  dyestuff  are  those  actually  absorbed  in  the 
standing  bath,  and  the  starting  bath  has  to  be  charged  with  a larger 
quantity  of  dyestuff,  depending  on  the  volume  of  the  liquor. 

Of  Glauber’s  salt  and  soda,  about  one-quarter  to  one-fifth  the  quan- 
tities used  for  the  starting  bath  are  required  for  dyeing  of  the  subsequent  lots 

The  coupling  is  effected  by  treating  the  dyed  and  rinsed  cotton  in 
one  of  the  coupling  baths  prepared  with  Nitrazol  C or  Paranitraniline  C 
as  described  below. 

The  cold  coupling  bath  is  charged  successively  with  the  solutions 
of  Nitrazol  or  diazotised  Paranitraniline,  soda  and  acetate  of  soda;  in  this 
bath  the  cotton  is  treated  for  y2  hour  and  then  rinsed. 

When  coupling  in  dyeing  machines,  it  is  well  to  omit  the  soda  and 
acetate  of  soda,  and  to  increase  the  quantity  of  Nitrazol  or  Paranitraniline  by 
one-fourth  to  one-third.  It  is  an  advantage,  when  coupling  in  machines, 
particularly  in  packing  apparatus,  to  prolong  the  duration  of  the  coupling 
process,  adding  the  Nitrazol  in  two  to  three  lots,  if  possible  whilst  working 
the  pump  from  the  inside  towards  the  outside. 

For  shading  the  dyeings,  small  quantities  of  Basic  Colours  may  be 
added  to  the  coupling  bath,  e.  g.  for  Black  0.2 — 0.3%  Methylene  Blue  BB. 


a)  Coupling  with  Nitrazol  C. 
For  100  lbs  cotton. 


For  1% — 2%  dyeings  with 

For  3 — 4%  dyeings  with 

2 lbs  Nitrazol  C 

3 — 4 lbs  Nitrazol  C 

y2  lb.  soda  ash 

% — 1 lb  soda  ash 

3 oz  acetate  of  soda 

3 — 4 oz  acetate  of  soda. 

To  dissolve  the  Nitrazol  C,  it  should  be  stirred  up  with  a little  cold 
water  (20°  C.  or  68 — 77°  F).  Any  lumps  that  may  have  formed  should  be 
carefully  broken  up,  the  Nitrazol  being  finally  brought  into  solution  by 
pouring  a sufficient  quantity  of  cold  water  over  it. 


